Summary of the invention
The problem that invention will solve
Drive the steering swivel system of vehicle about conventional motors,patent documentation 1 has proposed to be equipped with the method that power steering system that the vehicle of driving engine (being also referred to as " internal combustion engine ") uses is used for not having the elec. vehicle etc. of driving engine.But the method produces the pseudo-engine speed of expression predetermined speed so that during receiving the startup ready signal that makes the electrical motor that travels that is installed on the elec. vehicle be in driving condition, thus the steering effort that should the puppet engine speed can assist the occupant.
At this moment, if should the puppet engine speed greater than described command speed, then be judged as driving engine and work, and the control of the power steering of executive basis car speed.
Yet; when vehicle velocity signal is lost, carry out in the power steering system of the type of controlling based on the fail safe of engine speed as fail safe; existent defect; because if pseudo-engine speed signal has fixed value, then can not carry out the fail safe function that the fail safe function with engine-driven vehicle is equal to.
The below describes the shortcoming ofpatent documentation 1 in detail.
(1)patent documentation 1 does not provide the explanation that pseudo-engine speed changes with the variation of the speed of driving motor, always and exist and provide the auxiliary worry of fixing steering effort.Under this state, the steering operation that possibly can't reach is equal to the steering operation of the vehicle that conventional engines only is installed.
(2) when producing pseudo-engine speed signal in the normal situation that produces vehicle velocity signal etc., carry out the auxiliary of steering effort normal, but therein in the situation of a signal forfeiture, can not carry out the auxiliary of steering effort.
(3)patent documentation 1 does not provide the explanation relevant with fail safe control.
The auxiliary quantity of steering effort adopts the fail safe control technology with the power steering system that the variation of car speed changes; wherein in the situation that can not obtain vehicle velocity signal; replace car speed to determine the auxiliary quantity of steering effort based on engine speed, and carry out the auxiliary of this steering effort.
When the power steering system that uses at the vehicle that driving engine will be installed was used for electric motor driven vehicle such as elec. vehicle, the steering operation for the steering operation that reaches with the vehicle that driving engine is installed is equal to still had room for improvement.
The steering swivel system that the purpose of this invention is to provide a kind of electric motor driven vehicle; it has the steering operation that the steering operation with the vehicle that traditional internal combustion engine only is installed is equal to, and even also has the steering operation that is equal to intrinsic steering operation carrying out the auxiliary fail safe control period of steering effort.
For the scheme of dealing with problems
Therefore, in order to overcome above-mentioned shortcoming, the invention provides a kind of steering swivel system of electric motor driven vehicle, this electric motor driven vehicle comprises: driving motor, and it is the propulsion source of described electric motor driven vehicle; Motor speed sensor, it is for detection of the speed of described driving motor; Steering swivel system, it is used for providing steering angle according to the steering angle of bearing circle to front-wheel; Vehicle speed sensor, it is for detection of the speed of described electric motor driven vehicle; And power steering controller, it is based in the output signal of described motor speed sensor and described vehicle speed sensor at least one, steering operation according to the occupant is exported auxiliary quantity, it is characterized in that, described auxiliary quantity is increased along with the speed of the speed of described electric motor driven vehicle or described driving motor and diminish.
The invention effect
Describe in detail as mentioned, according to the present invention, electric motor driven vehicle comprises: driving motor, and it is the propulsion source of described electric motor driven vehicle; Motor speed sensor, it is for detection of the speed of described driving motor; Steering swivel system, it is used for providing steering angle according to the steering angle of bearing circle to front-wheel; Vehicle speed sensor, it is for detection of the speed of described electric motor driven vehicle; And power steering controller, it is based in the output signal of described motor speed sensor and described vehicle speed sensor at least one, steering operation according to the occupant is exported auxiliary quantity, in the steering swivel system of this electric motor driven vehicle, described auxiliary quantity is increased along with the speed of the speed of described electric motor driven vehicle or described driving motor and diminish.
Therefore, the steering swivel system that the vehicle of traditional combustion engine uses only is installed can be used for electric motor driven vehicle, such as elec. vehicle, and further can reach the steering operation that the steering operation with the vehicle that combustion engine is installed is equal to.
The specific embodiment
Describe embodiments of the present invention in detail referring now to accompanying drawing.
Embodiment
Fig. 1 and Fig. 2 illustrate embodiments of the present invention.
In Fig. 1, the electric motor driven vehicle ofReference numeral 1 expression.
This electric motor drivenvehicle 1 comprises: drivingmotor 2, and it is the propulsion source of electric motor drivenvehicle 1;Motor speed sensor 3, it is for detection of the speed of drivingmotor 2;Steering swivel system 6, it is used for providing steering angle according to the steering angle ofbearing circle 4 to front-wheel (being also referred to as " drive wheel "); Vehicle speed sensor 7, it is for detection of the speed of electric motor drivenvehicle 1; And power steering controller 8, it exports auxiliary quantity based in the output signal of describedmotor speed sensor 3 and described vehicle speed sensor 7 at least one according to occupant's steering operation.
In addition, as shown in fig. 1, electric motor drivenvehicle 1 has front-wheel 5 andtrailing wheel 9, and drivingbattery 10 is installed betweentrailing wheel 9.
Thedriving motor 2 that is installed between the front-wheel 5 drives by being connected to theinverter 11 that drivesbattery 10.
In addition, front-wheel 5 is driven with theaxle drive shaft 13 that is connected to a front-wheel 5 via theretarder 12 that is arranged between the front-wheel 5 by drivingmotor 2.
Be arranged near the drivingmotor 2 to be independent of the vehicle speed sensor 7 of the rotating speed of measuring this front-wheel 5 for detection of themotor speed sensor 3 of the speed of drivingmotor 2.
Therefore, electric motor drivenvehicle 1 is equipped with vehicle speed sensor 7 andmotor speed sensor 3 these two sensors independently, as the device of estimated vehicle velocity.
Use the driver's of bearingcircle 4 steering operation to be sent to the steeringswivel system 6 that is arranged between the front-wheel 5, thereby turn to.At this moment,power steering unit 14 auxiliary drivers' steering operation.
At this moment, thevehicle steering control 15 that is connected to inverter 11 and vehicle speed sensor 7 to send the driving torque instructions to inverter 11 according to by driving the driver's that operation information such as accelerator and gear-shift lever carry out operation.
In addition,vehicle steering control 15 calculates car speed according to the vehicle velocity signal that sends from vehicle speed sensor 7, and the car speed that calculates is sent to power steering controller 8.
This power steering controller 8 comes auxiliary control is carried out inpower steering unit 14 according to vehicle velocity signal.
In addition, power steering controller 8 is by judging whether engine speed signal has surpassed command speed and (be set as the idling that is lower than driving engine, for example, 600rpm) judge whether this state needs the steering effort of auxiliary bearingcircle 4.
Therefore, at the elec. vehicle that driving engine is not installed or in car speed and engine speed must not be mutually related the tandem hybrid vehicle, as the means of the auxiliary state of the steering effort that power steering controller 8 is knownneed bearing circle 4,vehicle steering control 15 provides the pseudo-engine speed signal that is not less than command speed.
If infer to a certain extent the car speed state in vehicle velocity signal forfeiture then according to engine speed signal and implement in the power steering system of type of fail safe control; if pseudo-engine speed signal is got fixed value, then the executive basis car speed is not implemented the auxiliary fail safe function of controlling of bottom line.
Therefore, the electromotor velocity signal thatvehicle steering control 15 sends based on themotor speed sensor 3 of installing from being independent of vehicle speed sensor 7 comes the Computation of Pseudo engine speed signal, and the signal that calculates is sent to power steering controller 8.
In addition, the steeringswivel system 6 of electric motor drivenvehicle 1 is configured to make auxiliary quantity to increase along with the speed of the speed of electric motor drivenvehicle 1 or drivingmotor 2 and diminishes.
Especially, the auxiliary quantity that makes steering effort increases along with the speed of the speed of electric motor drivenvehicle 1 or drivingmotor 2 and diminishes.
Therefore, the steering swivel system that the vehicle of traditional combustion engine uses only is installed can be used for electric motor driven vehicle, such as elec. vehicle, and further can reach the steering operation that the steering operation with the vehicle that combustion engine is installed is equal to.
Power steering controller 8 is set as speed along with drivingmotor 2 with the value of pseudo-engine speed to be increased and uprises, and power steering controller 8 is configured so that in the time can not obtaining output signal from vehicle speed sensor 7, power steering controller 8 is determined auxiliary quantity based on this puppet engine speed, and in the time can not obtaining output frommotor speed sensor 3, power steering controller 8 is determined auxiliary quantity based on the output signal that sends from vehicle speed sensor 7.
Especially, Fig. 2 is the figure that illustrates based on an example of the pseudo-engine speed of the speed of drivingmotor 2.
For engine-driven vehicle, difference in high car speed zone, reaches high engine speed although the relation between car speed and the engine speed depends on drive gear change, and in low car speed zone, reaches idling.
In the situation that shown in Fig. 2, in the low zone of the drive motor speed of the drivingmotor 2 that is associated with car speed (1000rpm among Fig. 2 or lower), pseudo-engine speed is got fixed value 800rpm, it is near idling.
In addition, within the drive motor speed of drivingmotor 2 surpassed the zone of 1000rpm, pseudo-engine speed is set as along with the increase of drive motor speed simply to be increased.
Especially, as shown in Figure 2, the drive motor speed of the 1000rpm corresponding with the pseudo-engine speed of 800rpm to the pseudo-engine speed of 6000rpm corresponding 10, in the scope of the drive motor speed of 000rpm, drive motor speed and pseudo-engine speed are set as has the relation that direct ratio increases.The drive motor speed corresponding with pseudo-engine speed can at random change.
Therefore, the steering swivel system that the vehicle of traditional combustion engine uses only is installed can be used for electric motor drivenvehicle 1, such as elec. vehicle, and can reach the steering operation that the steering operation with the vehicle that combustion engine is installed is equal to.
In addition; because car speed and two output signal systems of pseudo-engine speed being provided; each is the vehicle parameter for the auxiliary quantity of determining steering effort; so in the time can not obtaining one of them output signal; carry out fail safe control based on another output signal that sends from the sensor that works, and can obtain the auxiliary quantity identical with the auxiliary quantity that in the situation of the output signal that can normally obtain sensor, obtains.
The present invention is not limited to above-described embodiment, and can carry out variations and modifications.
For example, in embodiments of the present invention, vehicle speed sensor is used the device that acts on definite car speed; Yet this is an example, and can use the device that is used for determining car speed of any type.
In addition, if can normally detect car speed, then can determine based on the output signal of this car speed the auxiliary quantity of steering effort.Auxiliary quantity in the case is configured to along with the car speed increase and diminishes.
In addition, in the output signal forfeiture of car speed or the output signal forfeiture of electromotor velocity, and carry out in the situation of fail safe control, can use the information of the peculiar setup that shows the steering swivel system abnormality alarm to show.
Statement " the output signal forfeiture of the forfeiture of the output signal of car speed or electromotor velocity " refer to because vehicle speed sensor or the fault of motor speed sensor own and can not obtain the particular case of output signal, because line interruption and be not sent to situation etc. the situation of vehicle steering control, power steering controller etc. from the output signal that described sensor sends.
Description of reference numerals
1 electric motor driven vehicle
2 driving motors
3 motor speed sensor
4 bearing circle
5 front-wheels (drive wheel)
6 steering swivel systems
7 vehicle speed sensors
8 power steering controllers
9 trailing wheels
10 drive battery
11 inverters
12 retarders
13 axle drive shafts
14 power steering unit
15 vehicle steering controls